For some backstory, I was going to do the regi quest, and get Regice. Afterwards I planned on going to beat Lance boss, then towards cerulean cave and beat mewtwo, then continue the mew quest. I accidentally killed the Regice, so I went to battle Nikola. When battling Nikola, his first pokemon is Mewtwo, and even though I lost that battle, I got seen data for Mewtwo, and because of that, I dont need to beat Lance anymore, because I dont need cerulean cave. I don't exactly if this is supposed to happen, because I think as Mewtwo is Nikola's first pokemon, it's quite simple to get his seen data. I'm just reporting this because I didn't know if you're supposed to be able to get seen data like that, or if it has to be through the one in cerulean cave. I personally, feel as though you shouldn't be able to get seen data this way, but I was wondering if it was on purpose or not
EDIT: please don't go do this unless a mod says it's ok
EDIT2: also forgot to say this was all to get mew, and because I got the data from nikola, I went straight to catching mew
sry if it was unclear